The narrowleafed milkweed, Asclepias fascicularis, beckons monarch butterflies (the host plant), aphids, praying mantids and assorted other insects, but once in a while, you'll see a leafcutter bee. Both the plant and the bee are natives.
This male bee (below) spent the afternoon patrolling for females, but it rested in between.
It's a dangerous place to rest when there's a predator (praying mantis) around, but all ended well.
Leafcutter bees, spp., so named because the females cut leaves and petals (perfectly round holes!) to line their nests, are smaller than honey bees--and much faster. They're easily recognizable by the black-white bands on their abdomen.
The females do all the work. They gather pollen and nectar, make the nests from the leaf and petal fragments, and lay eggs. They seal the egg chambers with the leaves or flower petals.
The male's job is to reproduce. And sometimes, you'll see one sunning itself on a milkweed leaf.
Of the 4000 bee species known in the United States, about 1600 reside in California. The leafcutter bee is just one of them. The family, Megachilidae, includes these leafcutting bees, Megachile angelarum, M. fidelis and M. montivaga; the alfalfa leafcutting bee, M. rotundata; the Mason bee, Osmia coloradensis; and the blue orchard bee (BOB), Osmia lignaria propinqua.
For more information on California's bees, read California Bees and Blooms: A Guide for Gardeners and Naturalists (Heyday), the work of UC-affiliated scientists,/span>
She came, she saw, she oviposited, she nectared and she left.
That's the extent of our sole monarch sighting in our Vacaville pollinator garden this year. This occurred Oct. 9.
But the good news is that more monarchs are gathering on the overwintering sites along the California coast than this time last year. And this is occurring during a major drought year.
In an article, Monarch Butterflies Return to Pacific Grove. And the Drought May Be the Reason for Their Rebound, published yesterday (Oct. 21) in the San Francisco Chronicle, Tara Duggan wrote:
"For once there is some promising news for western monarch butterflies: Around 2,600 of the migratory insects were counted at Pacific Grove Thursday, after zero were observed at the famed Monterey County sanctuary last year. And overall, conservationists estimate the current population that has arrived in its annual wintertime migration to the California coast to be around 10,000 compared to 1,900 last year.
"One possible reason for the rebound: this year's drought, since warm and dry conditions in early spring can help with their migration."
Many others haves noticed the uptick, too. On Oct. 14, entomologist David James of Washington State University wrote on his Monarchs Butterflies of the Pacific Coast Facebook page: "Another exciting and encouraging update on monarch arrivals at the California overwintering sites. Combining all the reports I've received over the past few days there are an estimated 1500 butterflies at 5 overwintering sites from Santa Cruz to Pismo Beach. And still the butterflies are arriving... The highest number at one site is about 700 at a site in the Pismo beach area. This exceeds the highest number seen at one site in 2020 (550 at Natural Bridges). Pacific Grove is reported to have about 200 butterflies. This is especially notable since none were recorded at this site in 2020. Inbound migration will continue for a few more weeks yet but even at this early stage we are close to exceeding the entire population counted at overwintering sites in 2020. Good news, indeed!"
Volunteers counted only 1900 on the overwintering sites along the California coast in 2020, according to the Xerces Society for Invertebrate Conservation. Compare that to approximately 29,000 in 2019 and almost 200,000 in 2017.
"But on Wednesday (Oct. 20) volunteers counted 8,000 of the butterflies at two groves in Pismo Beach, compared to 300 last year," wrote Duggan.
Scientists, including Art Shapiro, UC Davis distinguished professor of evolution and ecology, say the main reasons for the decline of the monarchs are habitat loss and pesticides.
Plant milkweed, plant nectar sources and lose the pesticides.
(Editor's Note: Due to UC ANR server issues, images aren't visible. Click on the icon to see the image)
Hey, wait, take me with you!
No, leave me alone! Let me go!
Have you ever seen insects struggling to free themselves from the reproductive chamber of a milkweed blossom?
Instead of producing loose pollen grains, milkweeds produce pollinia, a waxy, sticky packet of golden pollen grains originating from a single anther. When bees and other insects forage for nectar in the "nectar troughs," where the pollinia are, they emerge with wishbone-shaped pollinia on their feet or other body parts. That is, if they emerge at all. Sometimes they die there; the reproductive chamber becomes a floral death trap.
What may seem like nature's appalling act of cruelty is actually a unique case of floral pollination, the transfer of pollina from one blossom to another.
"Milkweed flowers bloom in umbels which are clusters of individual flowers on stems that emerge from a common point," explains Eric Eldredge in an article published by the U.S. Department of Agriculture's Natural Resources Conservation Service. "Flowers of different species of milkweed differ in size, color, and fragrance, but all produce their pollen in waxy sacs called pollinia. The pollinia are located in two anther pouches adjacent to vertical stigmatic slits of the flowers. Pairs of adjacent pollinia are connected to each other by translator arms from a clamp located in the middle, called the corpusculum (Bookman, 1981). The complete structure is called a pollinarium."
"Insects that visit a flower to drink nectar struggle to grasp the slippery surfaces and may accidentally slip their leg, tarsus, mouthpart, or other appendage into the opening at the bottom of the stigmatic slit. This slit is formed by guide rails, which are lined with bristles that prevent the insect moving its appendage any direction but up. The top of the slit leads into the opening of the corpusculum, which has hard, sharp inside edges that taper together at the top. The corpusculum clamps firmly to the insect by pinching onto the insect's appendage. In its struggles to escape, if the insect is large enough, it can withdraw the paired pollinia from the anther pouches and fly away."
We've seen dead honey bees trapped in the milkweed blossoms while other bees forage around their carcasses. And then we've seen the frantic struggles (below). Fortunately this bee in the first three photos escaped. Another bee did not.
You've probably read the children's book, "Where's Waldo?"
Waldo wanders around the world, gets lost in the crowd or scenery, and it's your job to find him. Where'd he go?
If you have a praying mantis in your yard, you probably play "Where's Waldo?" a lot.
In our yard, it's "Walda." She's a gravid (pregnant) praying mantis and she never stays in one spot for long.
Camouflaged in the bushes, motionless, and deep in "prayer," she's a lost cause.
And then you see where she is. The Stagmomantis limbata. The bushes stir, and the next thing you know, she's gripping a bee in her spiked forelegs.
Right there. Right there.
Our showy milkweed (Asclepias speciosa) is putting on a show.
The towering plant--a good eight feet--anchors the garden as we patiently wait for monarch butterflies to arrive and lay their eggs.
It's mid-August and it appears the monarchs are not coming here to our little pollinator garden in Vacaville, Calif. Maybe we'll see some during their late summer or early fall migration--on their way to their overwintering sites along coastal California.
Meanwhile, the speciosa has more than its share of lady beetles (aka ladybugs) and aphids.
But now we have a new visitor, well, maybe a permanent resident.
A praying mantis, Stagmomantis limbata (as confirmed by mantis expert Lohit Garikipati, a UC Davis graduate and Bohart Museum of Entomology associate now attending graduate school in Towson University, Maryland) has arrived.
For the first several days, Ms. Mantis hung upside down and did not eat (at least in our presence). She watched the bees buzzing around but made no effort to snag one. We think she was yawning. "Okay, I know you're there. I don't care and I'm not hungry."
Then we found her exoskeleton on one of the speciosa leaves.
A mantid's "skeleton," you know, is outside its body and it's known as an "exoskeleton." It reminds us of a suit of armor, for protection, support and form (is it a "suite of amour" when love abounds?).
A young mantis eats and outgrows its exoskeleton and then it molts (sheds it). Scientists say some species of growing mantids may lose their exoskeletons as many as 10 times.
And, according to Garikipati, a mantis that has just molted may not eat for two or three days.
Did you hear that, bees?
So, bottom line, no monarchs on the milkweed.
But we do have assorted lady beetles, aphids, and one praying mantis and her exoskeleton.
Wait, correct that. Just one mantis. A breeze just swept away the exoskeleton.